In an excellent piece of historical research and economic exposition, two economics professors, Robert A. McGuire of the University of Akron and T. Norman Van Cott of Ball State University, have provided independent evidence for Thomas J. Dilorenzo’s thesis that tariffs played a bigger role in causing the Civil War than slavery.
In The Real Lincoln, DiLorenzo argues that President Lincoln invaded the secessionist South in order to hold on to the tariff revenues with which to subsidize Northern industry and build an American Empire. In "The Confederate Constitution, Tariffs, and the Laffer Relationship" (Economic Inquiry, Vol. 40, No. 3, July 2002), McGuire and Van Cott show that the Confederate Constitution explicitly prohibits tariff revenues from being used "to promote or foster any branch of industry." By prohibiting subsidies to industries and tariffs high enough to be protective, the Confederates located their tax on the lower end of the "Laffer curve."
The Confederate Constitution reflected the argument of John C. Calhoun against the 1828 Tariff of Abominations. Calhoun argued that the U.S. Constitution granted the tariff "as a tax power for the sole purpose of revenue — a power in its nature essentially different from that of imposing protective or prohibitory duties."
McGuire and Van Cott conclude that the tariff issue was a major factor in North-South tensions. Higher tariffs were "a key plank in the August 1860 Republican party platform. . . . northern politicians overall wanted dramatically higher tariff rates; Southern politicians did not."
"The handwriting was on the wall for the South," which clearly understood that remaining in the union meant certain tax exploitation for the benefit of the north.